1. Field of the Invention
Embodiments relate to a method of transmitting a frame and a communication device for performing the same, and more particularly to a method and a device allowing a plurality of communication devices participating in interference alignment to simultaneously transmit training symbols.
2. Description of the Related Art
In general, a local area network (LAN) that is a near field communication network is divided into a wired LAN and a wireless LAN (WLAN). The WLAN employs a method of performing communication on a network using propagation instead of using a cable. The WLAN has been introduced as an alternative for overcoming difficulties found in installation, maintenance and repair, and movement by cabling. An increase in mobile users is further accelerating a need for the WLAN.
A WLAN system includes an access point (AP) and a station (STA). The AP is a device which transmits radio waves such that STAs within a service range access the Internet or use a network. The wireless LAN follows an Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard established by the IEEE.
A basic configuration block of a WLAN system defined in IEEE 802.11 is a basic service set (BSS). A BSS may include an independent BSS in which STAs in the BSS perform direct communications with each other, an infrastructure BSS in which an AP is involved in communications between an STA and an STA inside or outside the BSS, and an extended service set which connects different BSSs to extend a service area.
Generally, an IEEE 802.11 based-WLAN system accesses a medium based on carrier sense multiple access/collision avoidance (CSMA/CA) and allows APs to operate independently. That is, in the WLAN system, an AP independently selects a communication channel by an operator or a channel allocation algorithm. Thus, in the presence of multiple WLAN systems, communication channels used for respective BSSs are highly likely to overlap. When communication channels overlap, possibility of interference occurring between adjacent BSSs is high, causing deterioration in network performance. Thus, there is a need to efficiently reduce interference in a WLAN system.